Multiple outlet electrical connector plug



March 21, 1950 HARPSTER 2,500,987

MULTIPLE OUTLET ELECTRICAL CONNECTOR PLUG Filed Feb. 12, 1946 ,9 mini 1 I 6%? flax aster INVENTOR J0 (/l 1 BY 4 i" ATTORNEY Patented Mar. 21, 1950 UNITED STATES PATENT OFFICE MULTIPLE OUTLET ELECTRICAL CONNECTOR PLUG 3 Claims.

This invention relates generally to multiple outlet electrical plugs adapted to make electrical contact with one or more electrical plugs and more specifically to a multiple outlet electrical plug adapted to function as a plurality of male or female electrical outlets or a combination of both.

In the prior art there have been numerous multiple outlet electrical connecter plugs. However, all of such prior art plugs have had numerous disadvantages, among these being complex and expensive construction, low current carrying capacity when all of said outlets are connected, and low heat dissipating capacity. Numerous other disadvantages are also inherent in said plugs.

It is desirable in a multiple outlet electrical plug to have a plurality of outlets, any one of which may at the time of assembly be selectively made either a female or male outlet. It can readily be seen that if the manufacture of both a male and female multiple outlet plug or a plug with part and part female outlets is exactly the same, with the only difference being the final assembly operation, standardization and low manufacturing cost will be achieved. This is extremely desirable since most of the prior multiple outlet plugs have not had such standardization and have been relatively expensive to manufacture.

It is also extremely desirable in a multiple outlet electrical connecter plug to have the plug so designed as to be able to carry a heavy current such as, for' example, when one outlet is connected to a source of electrical power and all of the other outlets are connected to various loads. This can best be achieved by having the portions of the electrical connecter plug which carry the combined total current of all of the various individual outlets of sufficiently low resistance and with suiiiciently high heat dissipation rate as to cause the plug to operate in a safe range. Most of the prior art multiple outlet connecter plugs have been deficient in this very point, that is the portions of said plugs carrying the full maximum total current of each individual outlet were of fairly small cross-sectional area and therefore with high electrical resistance and with low heat dissipation.

Furthermore, most of the prior art multiple outlet electrical plugs were either manufactured as a plurality of male outlets or as a plurality 'of female outlets or a combination of both with different basic structures for the different plugs. It is also extremely desirable tolpositively prevent the possibility of an arc-over or a short occurring between electrical terminals of opposite polarity. Most of the prior art multiple outlet electrical connecter plugs did not positively prevent the possibility of such a short or arc-over.

Also, most prior art multiple outlet electrical connecter plugs did not provide a large number of available outlets conveniently located for ready usage.

With the above points in mind, it is an object of this invention to provide a multiple outlet electrical connecter plug wherein the various outlets may be either male or female and wherein at the time of assembly the various outlets may selectively be made male or female.

It is a further object of this invention to provide a multiple outlet electrical connecter plug readily adapted for heavy current carrying capacity.

It is a further object of this invention to provide a multiple outlet electrical connecter plug with a large heat dissipating capacity.

It is a further object of this invention to provide a multiple outlet electrical connecter plug wherein the portion carrying a maximum current has an extremely low electrical resistance.

It is a further object of this invention to provide a multiple outlet electrical connecter plug adapted to receive male prongs and wherein the contact resistance existing between said male prongs and the electrically conductive element contained in said plug is at a minimum because of a large surface area of contact between said members.

Referring to the drawings:

Fig. 1 is a perspective view of a preferred embodiment of my invention.

Fig. 2 is a top plan view of the bottom outer member portion of the plug of my invention with the metallic, electrical distributor and a prong in assembled position.

Fig. 3 is a front elevation, partly in section, of the assembled plug taken along the plane III-III of Fig. 2.

Fig. 4 is a front sectional elevation of half of an assembled plug taken along the plane IV--IV of Fig. 2.

Fig. 5 is a top plan view of the central prongspacing core member of my invention taken along the plane VV of Fig. 3.

The plug body comprising the outer members and the central core member may be made from Bakelite, rubber, plastic, or any other suitable insulating material. The central metallic dis tributor disc and the prongs may be made from spring brass or any other suitable electrically conductive resilient material. The hollow eyelet for joining the plug together may be made of any of the materials well known in the art utilized for such purposes.

More specifically, substantially hexagonalshaped, outer members i are each provided with an annular recess 2'. Each hexagonal face of each outer member 2 is provided with a radially directed, prong-receiving aperture 3 extending into said annular recess 2. Each of the outer members i is provided with cooperating locating means l which, in the example shown, comprise holes or indentations in the inner surfaces of each of said outer members i.

Mounted in the annular recess 2 of each outer member i is a unitary metallic electrical distributor disc 5 provided with six inwardly extending, resilient fingers 6, each of said resilient fingers 6 being provided with prong-engaging means I or dimpled protuberances as shown in the example illustrated, on the convex or inward side thereof. Each of said distributor discs is also provided with suitable locating means or cooperating locating means 8 cooperating with like means 9 on each outer member i for fixing each of the disc members 5 with respect to the outer members i.

A central, substantially hexagonal-shaped, prong-spacing, core member H3 is provided with suitable cooperating locating means H, which in the example shown, are buttons or protuberances, and is mounted between the two outer members i so that the cooperating locating means 4 and H cooperate to fix the relative position of the outer members i and the central core member ill. The relative position of said central core member iii and the outer members I is such that thick, radially extending portions ll! of core member iii are placed opposite the prong-receiving apertures 3 in the outer members i. The relative position of the central distributor disc 5 with respect to the core member ill and outer members I is such that each of the six resilient fingers 6 is opposite the prongreceiving apertures 3 in the outer members I.

The central, prong-spacing, core member H) in the example shown is provided with recessed portions it between the thick, radially extending spokes l2 and a thick, outer, circumferential portion M. Said recessed portions 13 are recessed on each side of core member it so. that only a web of material remains separating the two sides of the plug at the recessed portion 13. The outer body members I and the central core member [9 are centrally apertured and are joined together through said central aperture by means of hollow eyelet 15, said eyelet l5 being peened over on each end so as to rigidly join the plug assembly together.

If it is desired to have a multiple outlet plug having five female outlets and one male terminal for connecting to a suitable female outlet operatively connected to a s urce of electrical power, prongs it are inserted into the two opposing, prong-receiving apertures ii in one hexagonal face of said plug on opposite sides of the thick, radially extending portion l2 of central core member it Each of said prongs it in the example shown comprises half hardv brass in strip form, the outer end of which is bent back upon itself and which is perforated or partially perforated so as to engage the usual prong-engaging means generally found in a female electrical outlet. The

til.

inner end of each prong I6 is also bent back so as to diverge from the longitudinal axis of the prong I6. The diverging portion or resilient retaming means l8 acts to lock or retain the prong 16 within the recess 2. The inner end of the prong I6 is also provided with a hole or indentation 69 which cooperates with the dimpled protuberance i on the resilient finger B of the metallie distributoridisc 5, thus causinga firm engagemerit and electrical contact to take place.

It can readily be understood that when the male prongs of other male electrical terminals are inserted in the prong-receiving apertures of the other five faces of the plug, the holes generally provided in the ends of the prongs will also engage the dimpled protuberances l on the resilient fingers ii of the disc member 5, thus making firm electrical contact with said male plugs.

It is to be clearly and distinctly understood that the embodiment oi my invention illustrated and described herein is exemplary only- The plug, for example, need not'be. hexagonal; it may be polygonal or any other desired shape. The central, prong-spacing core need, not have recesses I3 therein. The locating means and cooperating. locating. means 4, i 1., 8, and a may take numerous forms. As an example, the cooperating locating means 8- and 5- maybe so placed as to cause cooperation between, metallic disc member 5- and. central prong-spacing, core member l-ll, rather than between disc member and outer members i. The central, metallic, distributor disc need not be of disc form but may take any one of numerous forms. The retained prongs. It may be one of numerous types of construction well known in the art. For example, they may be single strips of metal with. or without perforations or partial perforations therein and not bent back upon themselves as in the example illustrated, and described herein. Furthermore, said prongs and. prong-receiving apertures. into which they are fitted may be larger than usual since they will. be required to carry the total current being distributed through a plurality of out.- lets. Electrical supply line wires. may be connected in any suitable manner directly to the re tained prongs prior to. the insertion of.- said prongs into. the pron receiving apertures. Said connections between said electrical supply line wires and said retained prongs may be covered with any suitable insulating. material which willsnugly engage said prong-receiving, apertures-.. Many other variations are possible also. The. hollow eyelet member. l5 may be a hollow rivet having a. head at one end and having the other end peened over or itmay take numerous other forms. The outer member may be recessed so that said eyelet member i5. will fit fiush. The center core member might have recesses in eachside thereof for mounting the. electricalv distributor members with their convex sides. outward. In such. case, the. outer members could either be. of uniform thickness throughout or could be provided with spaced webs and radial spokes similar to those shown in the center core member in the. attached drawings.

It can be seen that I have provided a unique plug having an extremely low inherent electrical resistance, having a large contactarea, one which is capable of dissipating heatrapidly because of the; large area and numerousapertureswhich also act as ventilating means, and one which is of very simple, light, cheap construction readily adapted to-massproduction methods.

It is. try.- be clearlyand distinctly understood that my invention is not to be construed as limited by the specific examples and illustrations given herein but is to be limited only by the scope of the appended claims.

I claim:

1. A multiple outlet electrical plug comprising: a body provided with a plurality of angularly related sides, each side being provided with prongreceiving apertures, all of said apertures lying in a pair of spaced, parallel planes, said body comprising a central, prong-spacing core and a pair of outer members connected thereto, edges of said core and said outer members forming said angularly related sides; a recess between the prongspacing core and each of said outer members; a convex, disc-shaped, unitary, metallic, electrical distributor having a plurality of inwardly directed, resilient fingers formed in the distributor mounted in each recess, said resilient fingers being provided with prong-engaging means; and a plurality of prongs mounted in two or more of said prong-receiving apertures, the inner ends of said prongs being provided with resilient retaining means for retaining the inner ends of said prongs in said recesses in engagement with said fingers.

2. A multiple outlet electrical plug comprising: a polygonal body provided with a plurality of prong-receiving apertures lying in a pair of spaced, parallel planes, said body comprising a central, prong-spacing core and a pair of outer members connected thereto; a recess between the prong-spacing core and each of said outer members; a convex, disc-shaped, unitary, metallic, electrical distributor having a plurality of inwardly directed, resilient fingers formed in the convex distributor mounted in each recess; cating means formed integral with the core; cooperating locating means formed integral with the outer members and cooperating with said locating means formed integral with the core; distributor locating means formed integral with said distributor; cooperating distributor locating means formed integral with the outer members and cooperating with said distributor locating means; and a plurality of prongs mounted in two or more of said prong-receiving apertures, the inner ends of said prongs being provided with resilient retaining means for retaining the inner ends of said prongs in said recesses in engagement with said resilient fingers.

3. A multiple outlet electrical plug comprising: a body provided with a plurality of angularly related sides, each side being provided with prongreceiving apertures, all of said apertures lying in a pair of parallel, spaced planes, said body comprising a central, prong-spacing core and a pair of outer members connected thereto, the edges of said core and outer members forming said angularly related sides; a recess between the prong-spacing core and each of said outer members; a convex, disc-shaped, unitary, centrally apertured, metallic, electrical distributor having six inwardly directed, resilient fingers formed integrally in the convex distributor mounted in each recess, each of said resilient fingers being provided with a prong-engaging, protruding dimple; locating means formed integral with the core; cooperating locating means formed integral with the outer members and cooperating with said locating means formed integral with the core; distributor locating means formed integral with the distributors; cooperating distributor locating means formed integral with the outer members and cooperating with said distributor locating means; and a plurality of prongs mounted in two or more of said prong-receiving apertures, the inner ends of said prongs being provided with holes cooperating with said prong-engaging dimples and being provided with resilient retaining means for retaining the inner ends of said prongs within said recesses.

GLEN HARPSTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,503,306 Dominick July 29, 1924 1,633,025 Kranz June 21, 1927 1,734,073 Canton et al Nov. 5, 1929 1,882,791 Ferris Oct. 18, 1932 1,907,817 Hubbell May 9, 1933 1,950,717 Douglas Mar. 13, 1934 2,443,367 Aguilar June 15, 1947 

